Form frame is blacked out in Word 2010

[Paul1]

I have created a form in Word 2007 which is a part of a custom ribbon I have created.

The form is the GUI part of the .dotm file ribbon. The form contains a frame with 2 labels and a list box outside of the frame. These are populated using an XML file via VBA. In word 2007 everything works fine.

There is a problem when I save the .dotm file as a Word 2010 .dotm file and open the form in Word 2010. Then the frame part at the top of the form is blacked out. Please see attachments below.

I have no idea why. Everything else is working fine in the application. I would appreciate your help in solving this problem. Many thanks.

Note: I have blanked out the company name in the label for confidentiality purposes.